Gi\u1ea3i V\u1eadt L\u00ed 10 B\u00e0i 18 : C\u00e2n b\u1eb1ng c\u1ee7a m\u1ed9t v\u1eadt c\u00f3 tr\u1ee5c quay c\u1ed1 \u0111\u1ecbnh. Momen l\u1ef1c<\/a><\/blockquote><\/iframe>